look up any word, like cunt:
 
2.
The measurement of a persons level of horny.

scale is usually on a rate from 1-10, 10 being the horniest, 1 being the least
I'm a ten on the "Hornometer" and could use a good time.
by Jerry-Michael February 23, 2009
 
1.
A piece of jewelry that is capable of measuring the arousal level -- on a scale of 1 to 20, with 1 being completely asexual and 20 being insatiable -- of its wearer. A related component is also capable of adjusting the arousal level for desired effect. As outlined in the ebook, The Hornometer, by Joe Mudak
Jason wasn't sure if he should make a move on his girlfriend, so he quickly checked the readout on her hornometer. When he saw that it only registered an 8, he quickly raised her arousal level to 15.
by Joe Mudak October 05, 2013